@jillmvc,
This is what I've guessed so far. If you know I'm wrong- let me know.
Purple: Igneous Intrusive - Porphyry; the term porphyry refers to the purple-red form of this stone. Consisting of large-grained crystals such as feldspar or quartz.
White: Metamorphic – Quartzite; forms when a sandstone is altered by heat and pressure. Conditions recrystallize sand grains and silica that binds them together. Forms at convergent plate boundaries- sandstone is metamorphosed into quartzite while deeply buried.
Pink: Metamorphic – Quartzite; rocks stained by iron can be pink/red or purple. (Similar physical properties and feel to white quartzite)
Orange: Metamorphic – Quartzite; other impurities can cause quartzite to be orange, yellow, brown, green, or blue
Red/black: Sedimentary – Breccia; made up of angular to subangular, randomly oriented clasts of other sedimentary rocks. Produced by intrusive processes and associated with porphyry stocks.
Blue/green: Sedimentary – Breccia; made up of angular to subangular, randomly oriented clasts of other sedimentary rocks. Produced by intrusive processes and associated with porphyry stocks.